JPH06151406A - Supporting device of processed substrate and anode formation device provided with the same - Google Patents

Abstract

PURPOSE:To realize a quick disconnectable processed substrate supporting device capable of avoiding the leakage of process solution without fail at low cost within a formation vessel for chemical process by arranging the processed substrates in the process solution. CONSTITUTION:The supporting device of processed substrates is provided with an elastic sealing member 5 adhesively supporting the whole outer periphery excluding the process surfaces of the processed substrates 1, a substrate supporting jig 4 supporting the sealing member 5, a pressure feed adjusting device 40 wherein a gas or a liquid is externally fed to the hollow part 6 of the jig 4 is adhesively pressurize the sealing member 5 by the fluid pressure as well as the control means 40 controlling the deformation amount and the pressure amount of the sealing member 5 within a formation vessel for chemical process by arranging the processed substrates in the process solution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate supporting device for supporting a substrate to be treated in a treating solution, and an anodizing device provided with the same.

More specifically, the present invention provides a three-dimensional structure device in which functional elements such as a ULSI, a sensor device, an arithmetic element, and a memory in which a Bi-CMOS device having both low power consumption and high speed is mounted are stacked, or SOI (Silicon on Insulator) used for high voltage devices such as electronic exchanges, discharge printers, and power transistors for plasma displays.
r) The present invention relates to an anodizing device for a crystalline silicon layer used in the fields of forming technology and micromachining technology, and more particularly to an anodizing device used for producing porous silicon.

The porous silicon described in the present invention means
This means crystalline silicon characterized by having a single crystal structure and having a large number of pores inside.

The expression "crystalline silicon substrate" in the present invention means a single crystal silicon wafer having no pores used in the field of semiconductor industry.

[0005]

2. Description of the Related Art In recent years, semiconductor devices to which porous silicon is applied have been actively studied.

The formation of porous silicon is described by Willer (A.
Uhir) and Turner (DR Turner) in the course of research on the electropolishing of single crystal silicon biased to a positive potential in hydrofluoric acid (hereinafter abbreviated as HF) aqueous solution.

Then, by utilizing the highly reactive nature of porous silicon, it has been studied to apply the porous silicon oxide film to a device isolation process that requires the formation of a thick insulator in the silicon integrated circuit manufacturing process. FIPOS (Full Isolation)
by Porous Oxidized Silic
on), or silicon direct bonding technology for attaching a silicon epitaxial layer grown on a porous silicon substrate to an amorphous substrate or a single crystal silicon wafer substrate through an oxide film. It has been done.

The present inventor has already proposed an anodizing device having a cross-sectional structure as shown in FIG. 8 as a porous silicon etching treatment device for crystalline silicon using anodizing reaction.

In FIG. 8, 1 is a degenerated crystalline silicon substrate as a substrate to be processed, 2 is a chemical conversion tank made of tetrafluoroethylene resin (trade name: Teflon), 3a and 3b are negative and A platinum electrode plate to which a positive voltage is applied, 4 is a base supporting jig made of tetrafluoroethylene resin (trade name: Teflon) that constitutes the base supporting means, and 5 is a flexible, elastic, and airtight base. Base sealing material made of fluorinated ethylene resin (trade name: GORE-TEX), 11a
Reference numerals 11b and 11b are electrolyte solutions made of a hydrofluoric acid mixture, and 15 is a Gore-Tex base material support jig sealing member for keeping the chemical conversion tank 2 and the base material support jig 4 airtight.

Further, the conventional substrate supporting jig 4 shown in FIG.
9A is a perspective view for explaining the component structure of FIG. 9A, and FIG. 9B is a perspective view showing the shape after assembly. 4 in the figure
Reference numerals a and 4b are base body supporting jigs, and the crystalline silicon substrate 1
It has a separable structure for easy mounting and releasing.

Reference numerals 5a and 5b denote base support jigs 4a and 4
It is a Gore-tex base sealing material for inserting into the groove inside b to maintain airtightness with the crystalline silicon substrate 1, and is divided in the same manner as the base supporting jigs 4a and 4b.

The crystalline silicon substrate used in the semiconductor industry is subjected to orientation flat processing in order to show its crystal axis direction. For this reason, the divided base sealing materials (5a and 5b) and the base support jigs (4a and 4b) have an asymmetric shape.

Reference numeral 14 is a Teflon bolt for combining the base supporting jigs 4a and 4b, mounting the base supporting jigs 4a and 4b on the crystalline silicon substrate 1, and then pressing the base sealing members 5a and 5b. By completely tightening the bolt 14, the entire outer peripheral portion of the crystalline silicon substrate 1 and the joint surface between the substrate supporting jigs 4a and 4b are sealed with respect to the electrolyte solutions 11a and 11b.

After assembling the substrate supporting jig 4, a seal material 15 for the substrate supporting jig made of GORE-TEX is attached to the groove of the outer peripheral portion of the substrate supporting jig 4 and inserted into the chemical conversion tank 2 to form an electrolyte solution. 11a and 11b are hermetically and electrically separated.

Here, the anode side electrolyte solution 11b acts as a liquid electrode. Further, on the surface of the crystalline silicon substrate 1 on the side of the cathode-side electrolyte solution 11a, an electric barrier is generated due to the difference in work function between the electrolyte solution and the crystal silicon substrate. 8 indicates the direction of the chemical conversion reaction current.

Next, by using an external DC power source (not shown) to make the platinum electrode 3a a cathode and the platinum electrode 3b an anode, fluorine ions (hereinafter referred to as "F ^- ion") in the electrolyte solution 11a in the chemical conversion tank 2 Is abbreviated as “.” Occurs.
F ⁻ ions react with silicon atoms on the surface of the silicon wafer 1 on the cathode side to form silicon tetrafluoride (SiF ₄ ) and hydrogen (H ₂ ) to dissolve the silicon wafer 1 to form pores. .

It is known that the presence of holes in a silicon wafer plays an important role in the formation of pores by the anodization reaction of crystalline silicon. The formation mechanism is assumed as follows.

First, when the holes in the degenerate P-type silicon reach the surface of the single-crystal silicon wafer, a nucleophilic attack of F ⁻ ions on the Si—H bond that compensates the silicon dangling bonds on the surface occurs. Instead, a Si-F bond is formed.

Since the F atom has a higher electronegativity than the Si atom, polarization induction by the bound F ⁻ ion occurs,
Another F ⁻ ion attacks the surface Si—H bond to form further Si—F bond. As a result, H ₂ molecules are generated and at the same time, one electron is injected into the anode electrode. Si-
Due to the polarization generated by the H bond, a back bond (bac
The electron density of (k bonds) is lowered, and the Si—Si bond is weakened.

This weak bond (weaked bon)
ds) is attacked by HF or H ₂ O, Si atoms on the crystal surface become SiF ₄ and are released from the surface, and the surface is terminated with hydrogen or oxygen. The depressions on the crystal surface caused by the separation of Si atoms generate an electric field distribution that preferentially attracts holes, and the surface heterogeneity expands to form pores in the electric field direction.

In general, alcohol is often mixed with the electrolyte solution before use. This acts to prevent the hydrogen gas generated by the reaction from adhering to the surface and hindering the supply of hydrofluoric acid to the surface to hinder the reaction. Such preferential formation of pores also occurs in degenerate n-type silicon in which holes serve as minority carriers. In this case, generation of electron-hole pairs by irradiation with light serves as a hole supply source.

In the conventional anodizing apparatus, the electrolytic solution is electrically separated along the entire circumference of the beveled side surface of the crystalline silicon substrate 1, so that the negative electrode side surface of the crystalline silicon substrate 1 is uniformly porous. It can be qualitatively processed.

Further, the cross-sectional structure has a crystalline silicon substrate 1.
Since it is electrically symmetrical with respect to, by inverting the polarity of the voltage applied to the platinum electrodes 3a and 3b,
Both sides or the entire region of the crystalline silicon substrate 1 can be treated to be porous.

Furthermore, as shown in FIG. 10, a plurality of crystalline silicon substrates (1a-1d) are attached between the platinum electrodes 3a and 3b along the lines of electric force of the formation current and the substrate supporting jig (4a). .About.4d), it is characterized in that a large number of crystalline silicon substrates can be made porous at once by electrically separating them and disposing them at intervals.

[0025]

In the conventional anodizing apparatus, the electrolyte solution has a specific resistance of about 20 Ω · cm and also functions as a liquid electrode. Moreover, since the chemical conversion reaction proceeds due to the potential difference due to the electric barrier between the cathode-side surface and the anode-side surface of the crystalline silicon substrate, the chemical conversion tank and the substrate support jig other than the crystalline silicon substrate have excellent electrical insulation. It goes without saying that it should be composed of different materials.

Therefore, when assembling the base support jig, great care must be taken to prevent leakage of the electrolyte solution from the outer peripheral portion of the crystalline silicon substrate, the sealing material, and the joint portion of the base support jig.

In particular, when the electrolyte solution leaks in the vicinity of the crystalline silicon substrate, a current path is formed through the electrolyte solution, the potential difference decreases, and the chemical conversion reaction does not proceed in the vicinity of the leak point, and the leak point A region in which the crystalline silicon substrate is not made porous is locally generated around the center.

Such a variation in the in-plane distribution of the thickness of the porous silicon layer in the crystalline silicon substrate is not acceptable in the applied product of the porous silicon substrate and is a very serious problem.

From an industrial point of view, when a plurality of crystalline silicon substrates are collectively subjected to a porosification treatment, it is possible to reliably and easily support the substrate and prevent leakage of the electrolyte solution. is important.

However, the sealing material of the conventional example does not have a structure in which the entire circumference of the side surface outer peripheral portion of the crystalline silicon substrate is seamlessly sealed, so that there is a possibility that the electrolyte solution may leak from the joint portion of the substrate supporting jig. In addition, there is a problem that it takes time and effort to attach and detach the crystalline silicon substrate.

That is, conventionally, the substrate to be treated is surely prevented from leaking the processing solution, and the substrate to be treated is attached.
There is a problem to be solved that a supporting device for a base body having a simple structure that is easy to remove and can be reduced in cost has not been sufficiently realized.

(Object of the invention) Therefore, the object of the present invention is to prevent the leakage of the processing solution by the substrate to be processed, and at the same time, the substrate to be processed can be easily attached and detached and the cost can be reduced. It is to realize a support device for the substrate.

[0033]

As a means for solving the above-mentioned problems, the present invention provides a method for treating a substrate to be treated in a chemical conversion tank in which the substrate to be treated is placed in a treatment solution for chemical treatment. Supports in close contact with the entire circumference of the outer periphery except the surface,
A sealing material having elasticity, a substrate supporting jig that supports the sealing material, and a gas or liquid is injected into the hollow portion of the substrate supporting jig from the outside, and the sealing material is removed by the pressure of the fluid. A support device for a substrate to be processed, comprising: a device for pressing the substrate to bring it into close contact with the substrate; and a device for changing the pressure to control the deformation amount and the pressing amount of the sealing material. is there.

A chemical conversion tank for separating and holding the solution by the substrate to be treated, one or a plurality of jigs for supporting the substrate to be treated, and a jig for supporting an electrode placed in the solution. Is configured.

Further, the sealing material is an integrally formed member having no breaks over the entire circumference,
Further, in a chemical conversion tank in which a substrate to be treated is further supported in a treatment solution for chemical treatment, the jig for supporting the substrate to be treated comprises a heat-shrinkable tube, and the thermal contraction causes the substrate to be treated to be treated. A support device for a substrate to be treated, which is in close contact with and supports the entire circumference of the outer peripheral portion other than the surface, is used as the means, and a chemical conversion treatment is carried out by supporting the substrate to be treated in a processing solution. In the tank, there is provided a substrate support jig which is in close contact with the entire periphery of the substrate other than the surface to be processed and is pressed and supported, and which is made of an elastic tubular member having an inner diameter smaller than the outer diameter of the pressed portion of the substrate. It is characterized in that the inserted base body is pressed against and supported by the contraction force due to the elasticity of the tubular member on the entire circumference of the outer peripheral portion of the base body other than the surface to be treated. It is characterized in that it has a substrate supporting device and electrodes. The anodizing apparatus according to, it is intended to solve the above problems.

[0036]

According to the present invention, as a method of airtightly sealing the entire circumference of the outer periphery of the base body in accordance with the shape of the base body, it is possible to surely perform the treatment by using a seal member which is seamlessly integrated over the entire circumference. The leakage of the solution can be prevented.

The inner diameter shape of the sealing material is slightly larger than the outer diameter shape of the substrate to be processed such as the crystalline silicon substrate when the pressure is released, and when the pressure is applied, it is completely the same as the shape of the crystalline silicon substrate. The amount of deformation and the amount of pressing at this time should be the same or slightly smaller, and the amount of deformation and the amount of pressing at this time can be finely adjusted by air pressure or liquid pressure, so that the leakage of the solution can be reliably performed without damaging the substrate to be treated. Can be supported without.

By mounting such a highly elastic sealing material on the inner peripheral surface of the substrate supporting jig whose shape does not change due to the pressure, it is possible to repeatedly mount, seal and release the crystalline silicon substrate. .

Next, another sealing means of the present invention uses a thin tube having reversible or irreversible shrinkage due to heating as a sealing material.

The tubular sealing material has an inner diameter shape slightly larger than the outer diameter shape of the crystalline silicon substrate, and after the crystalline silicon substrate is inserted into the inside, the normal temperature of the crystalline silicon substrate is obtained. Shrink this in the direction
It is to seal.

In this case, the pressing can be finely adjusted by the heating temperature and the amount of shrinkage of the tubular sealing material depending on the heating time.

When a plurality of crystalline silicon substrates having the same shape are mounted on one tubular sealing material, they are heated and shrunk in order while being mounted one by one.

Further, if a stretchable sealing material having the same tubular shape as the outer diameter of the crystalline silicon substrate but slightly smaller than the outer diameter of the crystalline silicon substrate is used, the crystalline silicon substrate can be inserted into the inside while expanding. Thus, it is possible to seal by acting as a mechanical pressing force by the contraction force without depending on the thermal contraction.

That is, since these sealing materials seal the entire circumference of the side surface outer peripheral portion of the crystalline silicon substrate without interruption, the electrolyte solution does not leak from the joint portion of the substrate supporting jig as in the conventional example. Also, it is possible to easily attach and detach the crystalline silicon substrate.

[0045]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, specific embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 shows a schematic sectional view of an apparatus I according to Embodiment 1 of the present invention. In the figure, 1 is a crystalline silicon substrate as a substrate to be treated, 21a and 21b are electrode supporting jigs made of tetrafluoroethylene resin (trade name: Teflon), 3a
Reference numerals 3b and 3b are platinum electrode plates to which a negative and positive voltage is applied by an external DC power source (not shown), 4 is a base support jig made of tetrafluoroethylene resin (trade name: Teflon) that constitutes base support means, and 5 is the same. Flexible, elastic, airtight, and chemically resistant perfluoroelastomer
astomer) · Base material seal material made of rubber (trade name: Chemraz or Kalrez), 6 is a groove for mounting the base material seal material 5 and evenly transmitting air pressure or hydraulic pressure using the space Reference numeral 7 denotes a pressure supply port for supplying air pressure or liquid pressure from the external pressure supply system 40 to the space (hollow portion) formed by the groove 6 and the base sealing material 5. 8
Is an exhaust port for discharging the gas generated during the formation.
Reference numeral 9 is a tetrafluoroethylene resin having flexibility, elasticity, chemical resistance, and airtightness to prevent leakage of the electrolyte solution at the joint surface between the electrode support jigs 21a and 21b and the substrate support jig 4 (commodity). Name: Gore-Tex) sealant for chemical conversion tank, 1
Reference numeral 0 is a bolt for fixing the electrode supporting jigs 21a and 21b and the substrate supporting jig 4. 11a and 11b are electrolyte solutions composed of a hydrofluoric acid mixture.

Further, FIG. 2A is a sectional view for explaining the positional relationship immediately before mounting the crystalline silicon substrate 1 on the substrate supporting jig 4 of the present invention shown in FIG. 1 or immediately after releasing the mounting. Indicates. In the figure, since the pneumatic pressure or the hydraulic pressure is released, the inner diameter of the base sealing material 5 is larger than the outer diameter of the crystalline silicon substrate 1. In this state, the crystalline silicon substrate can freely pass inside the base sealing material.

Further, FIG. 2b shows a sectional view for explaining a state in which the crystalline silicon substrate 1 is mounted. In the figure, by supplying air pressure or liquid pressure from the pressure supply port 7, the base sealing material 5 is pressed along the taper of the groove 6 in the normal direction of the crystalline silicon substrate 1 to be projected. In the figure, the arrow indicates the direction of deformation of the base sealing material. Here, the taper of the base sealing material 5 and the groove 6 keeps the air pressure or the liquid pressure airtight, and the displacement of the base sealing material 5 with respect to the crystalline silicon substrate at the time of protrusion. It is also preferable because it prevents As the base sealing material, perfluoroelastomer rubber (trade name: Chemraz) having an elongation rate of 200% at room temperature was used.

In order to perform the porosification treatment of the crystalline silicon substrate in the device I of the present invention, first, boron (B) is doped to make the resistivity 0.01 to 0.02 Ωcm.
A (100) plane P-type crystalline silicon produced by the Z (Czochralski) method was subjected to orientation flat processing with a diameter of 125 mm and a thickness of 0.6 mm.
Used as the crystalline silicon substrate 1.

As the pressure applying means, compressed air having a pressure of 2 kgf / cm ² by a compressor (not shown) in the pressure supply adjusting device 40 in the figure was used. The shape of the base sealing material 5 is similar to that of the crystalline silicon substrate 1, but the inner diameter when the pressure of the compressed air is released is such that the crystalline silicon substrate 1 can freely pass therethrough. The opening was larger by 2 mm in diameter. However, the length of the straight line portion corresponding to the orientation flat portion of the crystalline silicon substrate 1 is 42.
It was set to 5 mm.

To bond the crystalline silicon substrate 1 to the substrate supporting jig 4, first, the flat surface portion of the crystalline silicon substrate 1 is adsorbed and supported by a vacuum chuck jig (not shown) in a state where the pressure of compressed air is released. It is located at the center of the base sealant 5.

Next, compressed air is added to the base sealing material 5, and this is deformed in the direction normal to the substrate. The pressure is adjusted by the pressure supply adjusting device 40 so that the base sealing material 5 is brought into close contact with and held on the entire outer peripheral portion of the crystalline silicon substrate 1. The vacuum of the vacuum chuck jig is released while maintaining this pressure.

In this state, the crystalline silicon substrate 1 and the substrate support jig 4 are integrally supported to ensure airtightness with respect to the electrolyte solution.

Electrode supporting jigs 21a and 21b are connected to both sides of the substrate supporting jig 4 through a chemical conversion tank sealant 9, and these are held by bolts 10.

The substrate supporting jig 4, the crystalline silicon substrate 1, and the electrode supporting jigs 21a and 21b form two electrically independent chemical conversion tanks.

48 wt. % (Weight percent) of pure water diluted hydrofluoric acid, pure water, alcohol 1: 1: 1
A mixed solution of hydrofluoric acid mixed at a rate of 10 is injected from the exhaust port 8, and the cathode side electrolyte solution 11a and the anode side electrolyte solution 11
b. The resistivity of the hydrofluoric acid mixed solution is 23.6Ω
cm.

Next, a current was applied to the platinum electrodes 3a and 3b at a current density of 8 mA / cm ² from a DC constant current power source (not shown).

At the same time when a current is passed, the chemical conversion reaction starts, and the formation of pores progresses from the surface of the crystalline silicon substrate 1 on the side of the cathode electrode 3a toward the surface of the side of the anode. Gases such as hydrogen formed during the porosification treatment are discharged from the exhaust port 8 to the outside of the formation tank.

When the porous silicon layer having a desired thickness is formed, the direct current is stopped, the electrolyte solution is discarded from the exhaust port 8, and pure water is injected into the chemical conversion tank instead to form the crystalline silicon substrate 1. To wash.

After discarding the pure water, the bolt 10 is loosened to separate the electrode supporting jigs 21a and 21b from the substrate supporting jig 4, and the chemical conversion tank is disassembled.

Next, the crystalline silicon substrate 1 is supported by a vacuum chuck (not shown), and the compressed air applied to the base sealing material 5 is released. The elastic base sealing material 5 is restored to its original shape, and the crystalline silicon substrate 1 is released.

A porous silicon layer having a thickness of 10 μm was formed in about 12 minutes. The thickness distribution of the porous silicon layer in the plane of the crystalline silicon substrate having a diameter of 125 cm was 10 μm at the center of the substrate and 11 to 12 μm at the outer peripheral portion of the substrate.

Porosity of the produced porous silicon: P
(Porosity) was 55%.

On the other hand, in the conventional sealing method, when the seal is incomplete and the electrolyte solution leaks,
A porous silicon layer is not formed at the leaked portion at all, and a chemical conversion reaction occurs as the distance from the leaked portion increases, and a porous silicon layer having a thickness of 10 μm is finally formed in a region separated by a radius of 40 mm from the leaked portion. Was done.

(Example 2) Next, Example 1 of the present invention will be described.
5 sets of substrate supporting jigs 4 that can be placed on the substrate were prepared, the intervals between the crystalline silicon substrates 1 were set to 50 mm, and a plurality of substrates were collectively subjected to chemical conversion treatment. The structure of the chemical conversion tank was the same as in Example 1 except that the substrates were arranged along the chemical conversion current between the platinum electrodes.

The formation conditions were the same as in Example 1 above, and only the applied voltage was increased in order to flow the same formation current.

The thickness of the porous silicon layer in the central portion of the formed five crystalline silicon substrates was 10 to 11 μm.

(Embodiment 3) The substrate supporting jig 4 in the first and second embodiments of the present invention utilizes the deformation of the substrate sealing material 5 by compressed air, but the reuse of the substrate supporting jig is considered. If not, the structure can be further simplified.

FIG. 3 shows a schematic cross-sectional view of the apparatus II of the embodiment of the present invention.

In the figure, 1 is a crystalline silicon substrate, 3a
And 3b are platinum electrode plates. 12 is a heat-shrinkable tube made of tetrafluoroethylene resin (trade name: Teflon),
8 is an exhaust port.

The outer diameter of the used crystalline silicon substrate 1 is 125 cm in diameter as in the first embodiment. The heat-shrinkable tube 12 has a thickness of 0.2 mm and its cross-sectional shape is shown in FIG.
As shown in FIG. 3, as in Examples 1 and 2, the inner diameter was 2 mm larger than the diameter of the crystalline silicon substrate to be used, and the linear portion had the same length as the orientation flat. The shape of the platinum electrode plates 3a and 3b,
And the dimensions were the same as those of the crystalline silicon substrate 1. That is, the platinum electrode plate and the crystalline silicon substrate are the heat-shrinkable tube 1
It is a size that can be moved within 2.

The platinum electrode plates 3a and 3b and the crystalline silicon substrate 1 are inserted into the heat-shrinkable tube 12 at intervals of 50 mm. After holding the platinum electrode plate and the crystalline silicon substrate from the outer wall of the heat-shrinkable tube 12 by a fixing jig (not shown), the heat-shrinkable tube 12 is heated to 177 ° C. to shrink it. The heat-shrinkable tube used in the apparatus II of the present embodiment has a heat-shrinkage rate of 77% at the heating temperature, and there is a surplus in easily compensating for the dimensional difference from the crystalline silicon substrate.

The heating is performed until the heat-shrinkable tube 12 is brought into close contact with the entire outer peripheral surfaces of the crystalline silicon substrate 1 and the platinum electrode plates 3a and 3b. After the heat shrinkage is completed, the fixing jig (not shown) is removed.

By the above operation, two electrically separated chemical conversion tanks are formed in the heat shrinkable tube 12 with a simple structure.

Next, the electrolyte solution was injected from the exhaust port 8,
A direct current is applied to each of the platinum electrode plates 3a and 3b to make the crystalline silicon substrate porous. Since the heat-shrinkable tube has high electric insulation and the outside of the heat-shrinkable tube is insulated with air, there is no leakage of direct current if the seal is completely performed.

The entire heat-shrinkable tube can be immersed in a liquid having a high electric insulation property, for example, pure water. This is particularly useful as a safety measure to prevent the platinum electrode plates 3a and 3b from being unintentionally released by the water pressure of the electrolyte solution.

However, care must be taken so that pure water does not flow into the chemical conversion tank through the exhaust port 8 and change the mixing ratio of the electrolyte solution.

Since the heat-shrinkable tube is transparent, it is possible not only to confirm the holding and sealing states of the crystalline silicon substrate, but also to visually observe the surface of the substrate during the chemical conversion and the inside of the chemical conversion tank.

When the treatment is completed, the electrolyte solution is discarded as in the above embodiment.

Here, the shrinkage of the heat shrinkable tube uses irreversible deformation due to heating. Therefore, when releasing the crystalline silicon substrate and the platinum electrode plate, it is difficult to use thermal deformation, and the heat-shrinkable tube was cut to release them.

(Fourth Embodiment) Next, a method of supporting the substrate by the contracting force due to the elasticity of the expanded tube, which is the reverse of the third embodiment, will be described.

FIG. 6 is a schematic sectional view of the apparatus III of the embodiment of the present invention.

In the figure, 1 is a crystalline silicon substrate similar to that used in Examples 1 to 3, and 13 is a perfluoro having an inner peripheral dimension slightly smaller than the outer peripheral dimension of the crystalline silicon substrate 1.・ An elastic tube made of elastomer / rubber (trade name: Chemraz). A tube having an elongation rate of 200% was used and its wall thickness was 2 mm.

Since the tube shape can be freely deformed, its sectional shape may be circular.

The inner diameter of the openings at both ends of the elastic tube 13 was made larger than the outer peripheral dimension of the crystalline silicon substrate so that the crystalline silicon substrate 1 could be easily inserted into the tube. 8 is an exhaust port.

FIG. 7 shows platinum electrodes 3a and 3b in the elastic tube 13 in the device III of the embodiment of the present invention.
FIG. 3 is a schematic cross-sectional view showing a state in which the crystalline silicon substrate 1 is inserted and supported.

The platinum electrodes 3a and 3b and the crystalline silicon substrate 1 are sequentially supported by a vacuum chuck (not shown),
The elastic tube 13 is inserted while being expanded.

At this time, since the elastic tube 13 tries to shrink to its original state, it adheres to and supports the entire area of the outer peripheral surface of the platinum electrode and the crystalline silicon substrate.

Next, as in the apparatus II of the embodiment, the exhaust port 8
An electrolyte solution is injected into the platinum electrode, and a direct current is applied to the platinum electrode to cause a chemical conversion reaction.

When the porosification treatment of the crystalline silicon substrate 1 is completed, the electrolytic solution is discarded.

Contrary to the above insertion, the platinum electrodes 3a and 3b and the crystalline silicon substrate 1 are supported by a vacuum chuck (not shown) and pulled out from the end of the elastic tube 13 to release it. .

After pulling out the crystalline silicon substrate 1 and the platinum electrodes 3a and 3b, the elastic tube 13 is restored to the size before insertion. Therefore, it can be used again.

Also in the embodiment apparatus III of the present invention, in order to cancel the liquid pressure of the electrolyte solution as in the case of the embodiment apparatus II, the embodiment apparatus under chemical conversion may be immersed in pure water.

Although not shown, the present invention can be realized by using an elastic plate having a similar opening in addition to the elastic tube used in the device III of the embodiment. In this case, the elastic plate is tightly sandwiched and supported by a Teflon plate having a similar opening.

In the above embodiment, the size of the crystalline silicon substrate may be any size that corresponds to the amount of deformation of the substrate supporting jig, and the size of the crystalline silicon substrate is limited by preparing a dedicated substrate supporting jig. Not a thing. Therefore, the shape is not limited to the circular shape.

The shape of the substrate to be treated is not limited to the plate shape, but may be a spherical shape or a cubic shape with a limited chemical conversion region.

Further, the apparatus of the embodiment of the present invention can be used for chemical conversion reactions other than the porosification treatment of the crystalline silicon substrate, by appropriately selecting the type and mixing ratio of the electrolyte solution.

Furthermore, part of the substrate sealing method of the present invention can be easily used as a sealing method other than the electrolyte solution of the present invention, regardless of liquid or gas.

[0099]

As described above, according to the present invention,
By adopting a structure in which the entire circumference of the substrate to be processed is pressed and closely supported, a simple structure that securely prevents the processing solution from leaking and is easy to attach and detach the substrate to be processed and can reduce the cost A substrate supporting device can be realized, and particularly in the anodizing device, an effect of uniformly treating the substrate to be treated can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a device I as an embodiment of an anodizing device as an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view for explaining a substrate supporting method of the device I of Example of the present invention.

FIG. 3 is a schematic cross-sectional view of Example device II using another substrate supporting method of the present invention.

FIG. 4 is an external view of a heat-shrinkable tube used in Example device II of the present invention.

FIG. 5 is a schematic cross-sectional view illustrating a state in which a substrate to be processed and electrodes are supported by a device II of Example of the present invention.

FIG. 6 is a schematic cross-sectional view of Example apparatus III using another substrate supporting method of the present invention.

FIG. 7 is a schematic cross-sectional view for explaining a state in which a substrate to be processed and an electrode are supported by a device III of Example of the present invention.

FIG. 8 is a schematic cross-sectional view showing the structure of a conventional anodizing apparatus.

9A and 9B are a perspective view showing a component structure of a conventional base support jig and a perspective view showing a shape after assembly.

FIG. 10 is a schematic cross-sectional view of a conventional anodizing apparatus that processes a plurality of substrates.

[Explanation of symbols]

 1 Crystalline Silicon Substrate (Substrate to be Processed) 2 Chemical Formation Tank 3a, 3b Platinum Electrode 4 Substrate Support Jig 5 Base Material Sealing Material 6 Seal Material Groove 7 Pressure Supply Port 8 Exhaust Port 9 Chemical Composition Tank Sealing Material 10 Bolts 11a, 11b Electrolyte solution 12 Heat-shrinkable tube 13 Elastic tube 21a, 21b Electrode support jig 40 Pressure supply adjustment device

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Toru Takizawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Chiki Kobe 3-30-2 Shimomaruko, Ota-ku, Tokyo Kya Non-Incorporated (72) Inventor Takao Yonehara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (6)

[Claims] 1. A resilient seal which, in a chemical conversion tank for supporting a substrate to be treated in a treatment solution for chemical treatment, closely adheres to and supports the entire periphery of the substrate except the treated surface. Material, a base support jig that supports the seal material, and a gas or liquid is injected from the outside into the hollow portion of the base support jig, and the seal material is applied to the treated surface of the base material by the pressure of the fluid. A support device for a substrate to be processed, comprising: a means for pressing the outer peripheral portion of the substrate to bring it into close contact with the outer peripheral portion; and a means for controlling the deformation amount and the pressing amount of the sealing material by changing the pressure. 2. A chemical conversion tank for separating and holding the solution is constituted by the substrate to be treated, one or a plurality of substrate supporting jigs, and an electrode supporting jig arranged in the solution. The apparatus for supporting a substrate to be processed according to claim 1. 3. The apparatus for supporting a substrate to be processed according to claim 1, wherein the sealing material is an integrally formed member that does not have a break over the entire circumference thereof. 4. A chemical conversion tank for supporting a substrate to be treated in a treatment solution for chemical treatment, wherein a jig for supporting the substrate to be treated comprises a heat shrinkable tube,
A support device for a substrate to be treated, which is brought into close contact with the entire circumference of an outer peripheral portion of the substrate other than the surface to be treated by the thermal contraction to support the substrate. 5. A chemical conversion tank in which a substrate to be treated is supported in a treatment solution for chemical treatment, and the substrate is closely pressed and supported on the entire circumference of the substrate except the surface to be treated,
There is a base body supporting jig made of an elastic tubular member having an inner diameter smaller than the outer diameter of the pressing portion of the base body, wherein the tubular base body supporting jig is the base body placed in the tube,
A support device for a substrate to be treated, which has a structure in which a contraction force due to elasticity of the tubular member is in close contact with the entire circumference of an outer peripheral portion of the substrate except for a surface to be treated to support the substrate. 6. An anodizing apparatus comprising the support device for a substrate to be treated according to claim 1 and an electrode.